Quad 4 x 28 GBaud PAM-4 (56 bit) Receive CDR

The MASC-38040 is a Quad 28GBaud PAM4/NRZ CDR with Integrated Limiting Amplifier for use in optical module applications. Each includes a high-sensitivity limiting amplifier, a high performance CDR, and an output driver with programmable output swing and 2-tap de-emphasis. The MASC-38040 reference-free CDR retime at 25.78 GBaud to 28.9 GBaud and can be bypassed to support legacy or non-standard data rates. MASC-38040 can be powered with a single 1.8V power supply and each channel can be controlled through the two-wire I2C compatible interface. The MASC-38040 is available in a 5.2 mm x 5.2 mm QFN compatible package.

Product Specifications

Part Number
Quad 4 x 28 GBaud PAM-4 (56 bit) Receive CDR
Max Data Rate(Gbps)
Number of Channels
Package Type
Integrated CDR


  • Quad 28GBaud PAM-4/NRZ CDR with Integrated Limiting Amp
  • Low Power Consumption
  • High-Sensitivity Limiting Amplifier with Programmable Slice Level Adjust and LOS Threshold
  • Reference-free CDR with optional Bypass Mode
  • Horizontal and Vertical Eye Shaping
  • Individual Channel Programmability/Power Down
  • Extracted clock output Fb/2, Fb/8, Fb/32 or Fb/40 (Monitor clock)
  • Dedicate Alarm Pins to flag LOS or LOL on any channel
  • Programmable Output Swing, Mute and De-Emphasis
  • Supports -5°C to +95°C Temperature Range
  • ye Monitor, PRBS Generator and Checker

Technical Resources

Data Sheet

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Quad 28G PAM4 CDR with Limiting Amp